1.Field of the Invention
The invention relates to built in test equipment (BITE).
2. Description of the Prior Art
BITE circuitry is utilized in the prior art to provide the on-line error status of a plurality of signal lines on, for example, printed wiring boards utilized in electronic systems and subsystems. Traditionally, each line is monitored by separate dedicated built in test circuits that monitor the on-line error status of the line. BITE implementations usually require extensive hardware particularly when large numbers of signal lines to be monitored are involved. Typically the BITE circuitry may comprise 20% of the system resulting in excessively large and expensive designs. Additionally since, in the prior art, most BITE designs require separate dedicated hardware for each signal line monitor, the number of signal lines tested is limited. Another prior art approach to BITE is to combine logic chips into a gate array. Although this approach reduces hardware, the cost is excessive.